Multiple law enforcement sources told CNN the suspect is a man and that the arrest happened in South Florida. No additional information was immediately available about the suspect.

Earlier Friday, authorities intercepted suspicious packages intended for Sen. Cory Booker and former Director of National Intelligence James Clapper.

The packages are the latest to be sent to prominent Democrats and critics of President Donald Trump that were discovered earlier this week.

The FBI said Friday that the package addressed to Booker, a New Jersey Democrat, was discovered in Florida and is "similar in appearance to the others." Sources told CNN the package was addressed to the senator's Camden, New Jersey, office. Booker confirmed the package was intended for him but declined to comment further to CNN.

The package intended for Clapper also was addressed to CNN, a law enforcement official said. It was found at a New York City postal facility and was similar to the other packages, the official added.

The package arrived in a manila envelope with six US flag stamps, similar to other packages discovered this week. The return address is that of Florida Democratic Rep. Debbie Wasserman Schultz's Florida office, which was the address on packages intended for former President Barack Obama, former Vice President Joe Biden, billionaire and Democratic donor George Soros, actor Robert De Niro, former Attorney General Eric Holder, 2016 Democratic presidential nominee Hillary Clinton and former CIA Director John Brennan. There is no information that suggests Wasserman Schultz sent the packages.

Trump was being briefed on the latest developments Friday morning, White House press secretary Sarah Sanders said. As the developments unfolded mid-morning, the President tweeted about illegal immigration, a key campaign issue he's highlighted ahead of the midterm elections.

Nationwide manhunt

On Thursday, two law enforcement officials familiar with the investigation told CNN that the nationwide manhunt for the person or people who sent the potential bombs has led authorities to a mail facility in Opa-locka, Florida.

Law enforcement authorities are treating the bombs as a domestic terror matter. The motive is unknown, but the recipients are all prominent targets of right-wing criticism and, in many cases, of Trump himself.

Clapper, who has frequently criticized Trump, vowed to CNN Friday morning that he wouldn't be intimidated in light of the discovery.

"I do want to just echo one thing that John Brennan said and that this is not going to silence the administration's critics," Clapper said.